Telephone-exchange switch-board



(No Model.) I K C. W. ROSS .8v G. H. TWISS.

` TELEPHONE EXCHANGE SWITCH BOARD.

No..258,868.' TMJL Patented May 30, 1882-..

,gill

Euf.

UNITED STATES l PATENT OEEICE.

CHARLES W. ROSS AND GEORGE TWISS, OF COLUMBUS, OHIO, ASSIGNORS 'IO 'THE WESTERN ELECTRIC MANUFACTURING COMPANY, OF CHICAGO,

ILLINOIS.

SPECIFICATION forming part of Letters Patent No. 258,868, dated May 30, 1852.

Application filed March 20, 1882. (No model.)

To all whom it may concern: Y

Beit known that we, CHARLES W.Rss and GEORGE H. TWISS, of Columbus, Ohio, have jointly invented certain new and useful Improvements in Telephone-Exchange Switch- Boards, of w-hich the following is a full, clear, concise, and exact description.

Our improvements relate tothe arrangement of the switches and vannunciators upon the 1o switch-board and to the circuits of the telephone-lines.

Our improvements consist in placing the annunciator of each line directly over its switch, so that the shutter, when down, may'obstruct the plug-hole of the switch, and in the connections for the signal-battery and operators telephone with the ltelegraph-lines.

In the drawings, Figure 1 is a front elevation of a portion ot' a switchboard. Fig. 2 is 2o an angular perspective of a part thereof, a portion being in section of line m m' ot' Fig. 1. The rear end of the spring-jackis broken away. Fig. 3 is a parallel perspective, showing the connections of the operators outfit and the gen- 2 5 erator with the telephone-line in detail.

Like parts are indicated by similar letters of reference in the different figures.

The annunciators a b c d and the switches or springjacks e fg h are constructed in the 3o usual manner. When a subscriber sends a current to line the drop of his aununciator is thrown down, (see annunciators c 01,) and when a connection is made with the line by means of the ordinary flexible cord provided with a 3 5 terminal plug, the plug,wheninserted, moves the lever of the switch, so as to take off the ground of the subscribers line in the usual manner.

'i and lc are springs electrically connected 4o with the frame of the switch. The subscribers line is connected with the frame of the switch, as shown at l, and his circuit normally passes, as shown, by line m to spring n, thence to connecting-bar o and to spring p, and thence, through the electro-magnet q, to ground.

vr and s are pins of wood or other non-conducting substance, which are placed between springs n and springs 7c p, respectively, as shown.

t is the line ofthe operator-s outfit, and-termi- 5o nates in a contact point or pin,u, near spring i.V

n is the line'of the generator or signaling battery, and terminates in a contact point or pin, w, near spring k.

When a shutter falls the operator answers the call by pressing on spring k ofthe switch in the line of the annunciator. She thus takes off the ground by separatingspring p and bar o, and at the same time closes the calling-battery to line, contact being made between spring 6o 7o and pin or point w. By then pressing on springt the operators telephone-outfit is connected to line at point u, the ground being taken off by the non-conducting pin r' lifting spring n from connecting bar or strip o. The operator thus receives the order of the subscriber. The subscriber wanted is summoned by pressing upon the spring k of his switch.

His answer to the call throws down the shutter of his annunciator. The operator then, by 7o pressing upon his spring i, connects her outfit with the called subscriber, provided she wishes to inform him who hascalled. The two subscribers lines are then connected in one circuit through the vcentral ofce in the usual manner by means of plugs and flexible cords.

It is usual to place a clearing-out annunciator in the circuit of the cords connecting any two switches. Y

The operator may connect any two subscrib- 8o ers-S' and S2, for example, the two connected with switches e and h-as follows: On seeing the shutter of annunciator d fall she irnmediately presses on spring and .is told by subscriber S' that he wishes to talk with-sub- 8 5 scriber S2. She at once connects the two switches by means of a flexible cord with terminal plugs, and taps on springe' of the switch of S2, and then is read'y for the next call. It'

S2 should be busy, she would simply notify S of 9o the fact.

By the system heretofore used the operator must insertaplugin the spring-jack of the calling subscriber before she can connect her outL lit with his line, and inv casel the subscriber wanted should be engaged the plug must be removed. Thus when the connection asked for' cannot be had two motions are dispensed with by the use of my system, and in other cases the shutter is restored, as it were, by the sinne motion with which the plug is inserted in n. subscribers switch.

I claim l. The subseribers groundeircuit in combination with two contact-springs, one for connecting` with the operators outt, the other for takingoffthe ground, and an intermediate noncondueting pin whereby, when the former is depressed so as to connect with the operators outfit, the latter will be movedautomatically, so as to take off the ground.

2. The combination of the eirouit of n. telephoneline through the springjack and nnnnnciator to ground with two springs, one for connecting with the operators outtt, the other for connecting with the generator, and means whereby the ground is automatically teken oft 2o when either spring is depressed ,'as and for the purpose specified. v

3. rihe combination, upon the switch-board of n telcphoneexchange, of spring-jacks, one for cach line, each line passing through its springjaek to ground, and pairs of keys, one pnir for euch spring-jack, one key of earch pair for connecting to the operators outfit, the other for connecting with the generator.

4. The combination, upon the switch-hoard of n telephone-exchange, of spring-jacks, one for euch line, each line passing through its spring-jack to ground, and pairs of keys, one pnir for each sprngjack, one key 0f each pair forconnecting tothe operators outfit, the other for connecting with the generator, and means nt cach pair whereby the ground is automatically removed when either key is depressed.

CHARLES W. ROSS. GEO. H. TVVISS. Witnesses F. P. Ross, W. D. BRESNAHAN. 

